Cannabis 101

How to pass a drug test for weed–the ultimate guide
Presented ByPassYourTest.comPublished on February 10, 2021 · Last updated November 11, 2022

This article is brought to you by PassYourTest.

Chances are, you’ve landed here because you need to know how to pass a drug test. Despite a record 21 states having legalized adult-use cannabis and nearly 40 running medal marijuana programs, many states still allow employers to drug test their employees for cannabis and use a positive test as grounds for termination or exclusion from hiring. But don’t worry, we’ve got you covered with all the answers you need.

In this guide, we’ll discuss the different types of drug tests and how long they can detect drugs in your body, and what protections your state of residence offers for employees who test positive for cannabis. Learn what you can do right now to support your body’s detoxification and how to get weed out of your system in time for your drug test.

What are your state’s drug testing laws?

Before you freak out, do a little research on your local drug testing laws. Many states offer some protections for current and prospective employees if they test positive for cannabis. California and New York, for example, prevent discrimination based on a positive test, and some employees have successfully taken their cases to court to reinstate their employment.

However, it’s also fair to assume states with no cannabis legislation also come down hard on consumers. Check out our article on state-by-state drug testing laws to determine your next steps.

Which type of drug test do you need to pass?

There are four main types of drug tests used to detect alcohol and scheduled substances—including THC—in your system. They each have varying detection windows, so finding out what type of test you have to take as soon as possible greatly impacts your preparedness and peace of mind.

Urine test

Courtesy of PassYourTest

Employers use the urine drug testing method far more often than any other form due to its convenience and low cost. The most common urine analysis used can detect 50ng/mL (nanograms per milliliter) or higher of THC in your system. This means that you must have at least 50 nanograms of THC per milliliter of urine for the test to return positive. Because cannabinoids, including THC, bind easily to lipids in the body, even a couple of hits of a joint can remain detectable in the body for days afterward. 

This method of testing is the easiest to overcome by getting your THC levels below this threshold. The most common problem people face with a urine test is the time it takes to lower THC levels in your body.

Because urine tests often come with little notice, many people choose a detox drink to cleanse their system on the day of their test for quick results. Others who have a little more time often use a detox kit and program to permanently cleanse their system so they can pass a urine drug test anytime.

How long does THC stay in your urine?

If you smoke weed daily, it may show up in your urine for 30-45 days after your last session, and potentially longer. This varies based on what kind of cannabis products you consume and body factors, such as metabolism and body fat percentage.

The potency of the cannabis you consume also plays a role; someone who prefers concentrates and extracts over smoking joints may test positive for THC for up to 60 days due to the high concentration of THC. Light to moderate users (a couple of times a month to a couple of times a week) may pass their test in 15-30 days. See more information about detection factors below.

Blood test

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Blood testing is rather expensive and invasive (they require extracting blood from the subject), so it isn’t used often. Yet, if someone really wanted to find out how recently you’ve consumed THC, blood testing would be the most time-sensitive method of choice—blood tests are best for determining if someone is currently under the influence of drugs or alcohol and have a detection window of minutes to hours from the last use of substances.

THC hits the bloodstream within seconds after inhalation of flower, vape cartridge, or concentrate, and within an hour of ingesting an edible. In rare circumstances, a blood test may be administered by law enforcement. Using a permanent cleanser could help flush THC in your system for a blood test.

How long does THC stay in your blood?

Light cannabis consumers (less than once a week) will likely only test positive for THC in a blood test for 1-7 days after use. Heavy, chronic consumers may test positive for 45-60 days. 

Hair follicle test 

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A hair follicle test is the least forgiving of them all, as it can detect substances for many months after consumption—it’s also quite invasive. You need much more than a few strands, and these tests are nearly impossible to fake. Hair follicle tests are best for showing long-term patterns of use.

No matter what you read online, bleaching or shaving your head won’t negate your test results, as the metabolites of the substances get stored within the hair shaft. Additionally, some medications have been shown to produce false positives, so the most-trusted way to pass a hair follicle test is with a detox shampoo.

How long does THC stay in your hair?

Hair follicle testing can typically detect THC use for 90-120 days, but heavy users may show THC that dates back up to six months. Most hair follicle tests require an inch and a half of hair for analysis from multiple strands. What if you’re bald or have short hair? A larger surface area is collected on the head, or in some cases, body hair is perfectly suitable.

How to pass a hair follicle drug test with detox shampoo

Saliva test

Courtesy of PassYourTest

Saliva, or mouth swab testing, is not as common as urinalysis (urine testing). It’s often used as a way to catch suspected drug users in the act, as the detection window is quite short (usually up to 72 hours for cannabis). Law enforcement, for example, might use a saliva test if they suspect you are under the influence while driving. An employer may use one following a workplace accident.

Mouth swabs are gaining popularity because they are quick and less costly to administer and provide fast results. All you have to do is swab the inside of each cheek and mix it with a solution that will indicate the presence of THC. 

How long does THC stay in your saliva?

THC is only detectable in saliva for less than a week days after the last time you consumed it, although it’s possible for heavy users to have THC detectable up to 30 days after last use.

Reasons why THC stays in your system

The reality is, how much THC stays in your system and for how long varies from person to person. Everyone metabolizes THC a bit differently, but there are some indicators to help you analyze your personal situation.

Levels of THC in your body

Above all, dosage and frequency of use have the biggest impact on determining factors in how long weed stays in your system. Taking one hit of weed every now and then as opposed to smoking, dabbing, or ingesting every day is an obvious comparison, but the form factor matters.

Someone who eats 100mg THC edibles a few times a week will take a lot longer to pass a drug test than someone who takes a few hits off a joint each week due to how the body metabolizes edibles. Dabs, extracts, and concentrates are much more potent than straight flower, and their higher THC amounts can linger.

Body mass index

Body mass index (BMI) is a measurement of height and weight used to quantify overall tissue mass. Why is this important? As soon as the body processes THC, it becomes a THC metabolite. Because THC is a fat-soluble molecule, the metabolites bond to fat cells until they are eventually burned and excreted from the body. So, the higher your body fat percentage, the greater the amount of THC stored in your fat cells, even if you don’t necessarily feel high.

If two people consume the same amount of cannabis simultaneously, it’s likely that the person with more body fat will take longer to detox naturally. However, keep in mind BMI doesn’t always accurately predict body fat percentage, and there are exceptions to every rule.

Metabolism & overall health

Metabolism plays a significant role in THC detox. We know that THC metabolites are stored in the body’s fat cells, so to purge them from your system, you need to increase the rate of metabolization via exercise and focus on fat cells. This happens all the time with regular activity, but not everyone has the same rate of metabolism. Some people burn fat quickly, while others require extra effort. General health plays a role here, too. If you are chronically dehydrated, live a sedentary lifestyle, or are generally unwell, it can take longer to detox from THC.

Courtesy of PassYourTest

How to detox from THC for a drug test

When it comes to cannabis, you need a solid plan for making sure you can pass a drug test. There are plenty of options to consider.

Natural detox

First and foremost, stop using all cannabis products, including hemp-derived ones. Plan to stop any further consumption for at least 30 days to let your body flush it out and do what you can to support your system.  No weed, dabs, vape, edibles, tinctures, or any other kind of cannabis product (including CBD and delta-8 products) until after you’ve passed your test. 

Drink water 

Hydration helps your body work better and faster. Aim for half your body weight in ounces of water daily to keep your systems in optimal condition. You can also drink herbal teas, cranberry juice, and clear broths to help increase hydration. Stay away from sugary drinks, alcohol, and too much caffeine.

Get moving 

Time to pump your heart rate up! Kick up that exercise routine, try a new cardio class, and get back on the treadmill. Burning energy, sweating, and attacking fat cells lead to purging THC, so put on your sneakers and get to it. 

Consider your diet

No detox is complete without dietary adjustments. It’s time to go easy on your digestive organs and reduce or eliminate red meat, pork, dairy, sugar, wheat, and processed foods. Keep it clean with lots of leafy greens, fresh fruits, and vegetables. If you prefer animal protein, stick to grilled fish and poultry.

Watch the Leafly review of Nutra Cleanse 5-Day Detox Kit

Detox products

Once you know your timeline and type of test, you can select your detox products to further increase your odds of passing. PassYourTest offers detox programs designed to help you permanently cleanse your system or just get through your drug test without peeing dirty.

THC detox kits or detox drinks: Which solution is right for you?

Detox kits

Detox kits from PassYourTest are designed to completely cleanse your system of unwanted toxins. So long as you quit consuming cannabis and complete the detox program outlined above, you will remain clean indefinitely. But if you smoke again, you can and likely will fail a drug test.

The cleansers work best to prepare you for urine and blood tests, with a choice of a 5-day or 10-day detox. As soon as you complete the program, you should be able to pass a drug test anytime. Each program comes with home THC test kits so you can test yourself to verify you are clean when done. 

5-Day Extreme Detoxification Program
Courtesy of PassYourTest

This program is designed for people that have a high level of exposure to THC and consume cannabis or hemp consistently. It includes a pre-cleanse formula, a daily herbal supplement, easy instructions, and a detox diet menu to help your body rid itself of unwanted THC. Two at-home THC test kits are included.

Price: $109.95

Exposure: Light, moderate, or heavy 

Body fat: Low to average

Weight: Less than 200 lbs.

Timeline: Clean in 5 days  

10-Day Ultra Detoxification Program
Courtesy of PassYourTest

This cleansing program is designed for anyone that has a very high level of daily exposure, including heavy daily smoking, vaping, concentrates, or edibles. We also recommend this program for anyone weighing 250 lbs or more, regardless of the frequency of cannabis use. Three at-home THC test kits are included.

Price: $149.95

Exposure: Heavy to extreme (daily user)

Body fat: Average or high

Weight: More than 200 lbs.

Timeline: Clean in 10 days

Same-day detox drinks

Detox drinks are the go-to solution for anyone with limited time to prepare for a urine drug test, though it is not a magical cure that will ensure a negative test. Take the same-day detox drink 2-3 hours before your drug test. Once you take the product, it begins to work within 90 minutes and lasts up to 6 hours.

After that, THC will begin to circulate through your system again. This is designed as a temporary fix to pass your test in a pinch. Don’t consume any cannabis during this timeframe or it can disrupt the results, causing you to fail. 

Fail-Safe Kit
Courtesy of PassYourTest

This is the best option for heavy consumers with higher body fat percentages or anyone who wants to be certain they’ll pass on short notice. The Fail Safe Kit contains a highly concentrated liquid detox shot and 12 capsules that remove any present metabolites from your urine, offering you an up-to-six-hour window to pass a drug test.

Price: $89.95

Exposure: Heavy to extreme (daily)

Body fat: High

Weight: More than 200 lbs.

Timeline: Clean in 90 minutes. Results last up to 6 hours.

Clean Shot
Courtesy of PassYourTest

When you don’t want to go overkill, but just need the right amount of assurance, opt for the clean shot. This 2.5oz detox shot comes with just four capsules designed to cleanse your system quickly so you can pee clean.

Price: $59.95

Exposure: Moderate to heavy

Body fat: Average

Weight: Less than 200 lbs.

Timeline: Clean in 90 minutes. Results last up to six hours.

Home testing kits

Sometimes you just need a sanity check to ensure you are clean and clear from THC before your livelihood depends on it. If you’ve been detoxing naturally and need to be certain you’ll pass, check out an at-home drug test kit.

Single Panel THC Home Test Kit
Courtesy of PassYourTest

This is a simple ‘pass’ or ‘fail’ urine test that will let you know whether or not you’re clean within five minutes. It’s 99% accurate and tests THC levels above 50 ng/mL—the industry standard of THC testing.

Test-O-Meter THC Home Test Kit

This kit tests for the presence of various levels of THC in your urine. It’s the most sensitive instant home THC test kit on the market, with 99% accuracy in minutes. It tests for 15, 50, 100, 200, and 300 ng/mL levels so you can track your detox progress.

Still not sure what to choose? Take the PassYourTest quiz, and it will guide you to the best option based on your frequency of use, weight, type of test, and how long you have to detox.

How to use an at-home drug test

Synthetic urine

Some instances of using synthetic urine have been known to successfully cheat a drug test. However, it’s still very difficult to do, and you risk bigger trouble if you’re found out. Urine must test at the right temperature and pH and have standard levels of creatine within a normal range. If you have to take a supervised urinalysis, it can be much more difficult to fake.

If you are caught with fake urine you will likely face serious consequences. First, you will obviously fail the test, meaning you will lose the job or whatever the opportunity was that was your original reason for being tested. Secondly, and more seriously, you could be looking at a hefty fine or even jail time depending on your state.

Home remedies

We get it—drug tests are stressful and, at times, panic-inducing. The internet is full of crazy home remedies and bizarre tricks to help you cheat a drug test. There is no scientific evidence pointing to these as viable options for passing a drug test, and we do not recommend them. Here are some of the most common ones to be mindful of.


Certo is a type of fruit pectin used to make jams and jellies. The Certo detox method involves a very detailed process with huge margins of error. Any misstep in the supposed formula, and you’ll definitely fail your test. Ultimately, there is no proof that this method even works and, even when following the protocol exactly, many people have failed their drug tests.


Niacin is an over-the-counter B vitamin traditionally used to reduce blood pressure and manage healthy cholesterol levels. Proponents of the niacin detox claim that taking large doses can help you flush your system of THC. However, massive doses of niacin will almost certainly result in a diluted urine sample leading to a failed test. Plus, too much niacin can lead to serious side effects, including liver damage. 

Because there is no evidence that niacin is a reliable way to pass a drug test, it’s best to avoid this method.

Other internet home remedies that will not help you pass a drug test and possibly mess with your internal health are:

  • Apple cider vinegar (ineffective)
  • Lemon water (ineffective)
  • Cranberry juice (ineffective)
  • Baking soda (just, no)
  • Hydrogen peroxide (absolutely not, this is for cuts and scrapes)
  • Using your friend’s urine

When you really need to pass a drug test, it’s best to stick with trusted detox kits and detox drinks.

Do niacin, vinegar, or cranberry cleanse your system of weed?

Frequently asked questions about drug testing

Still have questions? We have answers.

How do marijuana drug tests work?

Once you consume cannabis, it enters your bloodstream. From there, it makes its way to the body’s soft tissues before THC metabolites settle into your fat cells. Once the fat cells are burned, those metabolites recirculate through the bloodstream until they are eventually excreted via urine and feces. The metabolites are traceable to varying degrees by drug tests in urine, saliva, blood, and hair. 

Can CBD and/or delta-8 lead to a failed drug test?

Unfortunately, yes. Most drug tests are not sophisticated enough to determine the cannabinoid’s source of origin. So even if you’ve been consuming hemp-derived cannabinoids like CBD, delta-8 THC, HHC, THC-O, or others, you could potentially fail a drug test meant to detect cannabis.

Moreso, any full-spectrum CBD product contains trace amounts of THC. Depending on your dosage and frequency of use, this could be enough to trigger a positive result.

How long does weed stay in your system?

There is no exact method to determine how long weed will appear on a drug test. It depends on your personal body composition, age, health, hydration levels, and most importantly, frequency of use and consumption method. Smoking weed once versus vaping daily will equate to varying detox times. It’s always best to over-estimate and leave as big a window for detox as possible to ensure a clean test. 

When do employers drug test new hires?

Generally, employers will wait until the end of an interview process to drug test new hires. Employers have to pay a lab to provide drug test results, so they’ll generally only make the investment in a drug test if they’re planning on hiring a prospective employee.

However, some states have legislation that protects prospective employees in some industries who test positive. Learn about your local laws here.     

Does gender or sex affect a drug test?

No, gender and sex have no bearing on the outcome or preparation for a drug test. Although men generally require a longer time to detox than women, that is due to the greater average weight amongst the male population. 

How much urine is needed for a drug test?

You’ll need at least 30ml for a standard drug test or 45ml for a collection by the Department of Transportation; federal employers have stricter guidelines. For context, the average human bladder can hold around 300ml. 

How long does it take to get drug test results?

A standard urine test will show results in one to two days, in most cases. Other tests, such as blood tests, can take as long as a week. Sit tight, and don’t panic, you’ll have your answer soon. 

What can cause a false positive on a drug test? 

There are many foods and perfectly legal products that can affect your test results. In addition to foods like poppy seeds and hemp-base products, a few prescription medications, like certain antidepressants and antibiotics, can cause false positives on a drug test. 

Over-the-counter pain relievers and diet pills can also be mistaken for illicit drugs in a urine analysis. Finally, false positives can come from second-hand cannabis smoke exposure, as well. So, if you’ve got a drug test coming up, ask your roommate to take it outside.

Don’t stress, trust quality

Thankfully, there seems to be consensus on one thing when it comes to detoxification—use trustworthy products. Home remedies are not going to be reliable. If your livelihood depends on a clean test, do you really want to rely on something that produces mixed results?

Instead of taking any risks, go with a product with a proven track record. The cleanse coaches at PassYourTest have been helping people cleanse their systems for 20 years. They are highly confident in their formulated cleansers, and all their products come with a 100% guarantee. Detox with a proven product leader and be in the best position to pass.
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